More and more surgeons tend to use surgical staples, rather than conventional sutures since the use of surgical staples and surgical staplers can make many complex procedures much simpler and thereby reduce operation time. Many types of surgical staplers have been devised for different procedures, including linear staplers.
Over time, linear surgical staplers have evolved with significant improvements. These instruments generally include a pair of jaws cooperating with each other and supporting anvil and staple cartridge, respectively. The instruments also include a driver within the cartridge casing that pushes all of the staples out simultaneously against the anvil to form the staples into a generally B-shape, suturing tissue together. In addition, these instruments include approximation mechanisms that allow the cartridge housing and anvil to move relative to each other to accept tissue therebetween. Finally, the instruments include a handle and an activating “firing” mechanism. A surgeon moves the driver forward to form the staples against the anvil by actuating the firing mechanism with a firing trigger.
Although such instruments can staple tissue well, there is still room for improvement. For example, the current linear staplers often use left and right handle plates in the form of frame plate to connect the jaws to the handle and a driving mechanism is received in a space formed by the handle plates. Since the space formed by the handle plates is open, tissue is prone to be damaged for being trapped in the space during the insertion and firing of the instruments. U.S. Pat. No. 4,527,724 discloses a disposable linear stapler, in which a separate spacer is provided between the left and right handle plates. The spacer closes the space to some extent. However, as a large number of components usually means higher product cost and lower reliability for medical instruments, that instrument is not preferable.
For another example, a conventional alignment and retaining pin takes the form of a slim pin/wire extending from a position near the proximate end (i.e., the end with the handle) of the instruments up to its distal end (opposite end to the proximate end) to facilitate the manipulation by a surgeon. As a result, this kind of slim pin/wire with a long length inevitably limits the strength and robustness of the instrument.
Besides, it is also desirable to enhance the cleanability of a disposable and reusable linear stapler while maintaining its performance to make the cleansing work (i.e. assembly, disassembly, cleaning, sterilization and the like) easier.
The present invention is directed to improvements in one or more aspects as set forth above.